The article describes a modified version of the OCAI for the purpose of diagnosing the organizational culture at health care facilities. The authors’ hypothesis suggested the diagnostic equivalence between the OCAI modified version and its translated (from English) version used in the Russian-speaking countries (created by K. S. Cameron and K. Quinn based on the Concept of Competing Values). To solve the tasks, a field test of the original version, an expert assessment of the problem statements, development of adapted statements, re-examination, assessment of the reliability and validity of the authors’ OCAI version were carried out. The results show that the OCAI version for healthcare institutions retains the meaning and significance of the original OCAI diagnostic parameters and has acceptable psychometric properties making it applicable in healthcare institutions of the Republic of Belarus.